The same 203 mm gun had very different readiness aboard Surcouf and the Suffren-class cruisers. The submarine needed roughly two and a half minutes from the order to begin firing, while a cruiser could use ready ammunition and respond in about one minute. The difference lay in the space, handling path, and readiness arrangements available in the two hull types. Fitting cruiser-calibre artillery to a submarine did not give it cruiser-like tactical responsiveness.
Notable Point · 1:11:29-1:12:03
Surcouf versus cruiser main-gun readiness
The same 203 mm weapon took far longer to bring into action aboard Surcouf than aboard a conventional cruiser with ready ammunition available.